If you spent last winter getting used to your heat pump's warm and steady airflow, get ready for round two: summer! The good news is that your heat pump was made for cooling too. It just needs you to switch it to the correct settings and you’re good to go! This guide will cover: How a heat pump cools How to switch your heat pump to COOL mode Easy-to-do passive cooling tricks Best settings for your heat pump that can actually lower your electricity bill this summer You can think of it as the summer partner to our guide on what to expect in your first winter with a heat pump. How Does a Heat Pump Work in Summer? Did you know that a heat pump doesn’t just do what it suggests? It can also be used for all your cooling needs as well. In summer, your heat pump basically becomes a high-efficiency air conditioner (a “heat pump ac system” if you will). In other words, a heat pump can also be used for cooling. It pulls warm air from inside your home and sends it over a refrigerant coil to extract the heat and humidity. The outdoor unit pushes this heat outside, cooling the inside of your home. Because heat pumps run on the same refrigeration cycle as a traditional air conditioner, the two often perform similarly in terms of cooling. The difference is that your heat pump is a year-round investment. Once Fall rolls around, that same reversing valve that let it cool your home all summer flips direction and starts heating it instead. This is a big part of why the government of Canada recommends heat pumps as one of the more efficient options for year-round comfort in Canadian homes. How to Switch Your Heat Pump to COOL Mode Most heat pumps have three modes: Heat Cool Auto For summer, you'll want to choose COOL specifically, instead of leaving it on AUTO, so the system doesn't try to guess between heating and cooling as the temperature shifts throughout the day. To change modes: Central heat pump systems: Switch to COOL mode directly through your thermostat. Ductless mini-split systems: Use your remote, select "Mode," then choose "Cool." If you have a multi-zone setup, repeat this for each indoor head, making sure that all heads are set to the same mode. Summer Tips for Heat Pumps: Get the Best Heat Pump Performance Set It and Forget It Just like during winter, heat pumps run most efficiently when they're left at a consistent temperature rather than adjusted constantly throughout the day. Frequent changes force the system to work harder to catch up, using more energy overall. Set your heat pump to a comfortable temperature (the best heat pump temperature range for your syetem is 21°C–23°C) to maintain the perfect balance between comfort and efficiency. Clean Your Filters Heat pump cleaning is vital to ensure an optimal heating and cooling system. A clogged filter is one of the most common (and easiest to fix) causes of a heat pump underperforming. Dirty filters restrict airflow, making your system run longer and less efficiently to reach the same temperature. This applies whether you have a central ducted system or a ductless mini-split, though the filter locations and cleaning steps differ slightly between the two. How to clean your heat pump filters: Clean or replace filters every 1 to 3 months during heavy summer use. Keep the outdoor unit clear of leaves, debris, and any obstructions. Optimize Fan Speed Higher fan speeds cool a space faster but can feel less comfortable in humid conditions since air moves past the coil too quickly to remove much moisture. A lower or automatic fan speed setting often does a better job of dehumidifying, which can make a room feel cooler and smoother even at a slightly higher temperature. Use a Smart Thermostat A programmable or smart thermostat lets you automatically raise the temperature when you're out of the house and bring it back down before you're home, without you having to remember to do it manually. It's one of the easiest upgrades for cutting cooling costs without sacrificing comfort. You can program your thermostat to adjust to your cooling schedules; e.g. set specific temperature preferences for different times of the day and days of the week. However, make sure the temperature adjustments are modest and not too steep. Ideal Settings for Your Heat Pump in Summer Setting Recommendation Occupied hours 21–23°C Away from home 23–25°C Fan speed Auto or Low, for better dehumidification Mode Cool Thermostat adjustments No more than 1–2°C at a time Tips to Keep Your House Cool This Summer Your heat pump does a lot of the work, but a few simple habits can take pressure off your system and keep your home comfortable between cooling cycles: Close blinds or curtains on sun-facing windows during the hottest part of the day to block that direct heat. Keep windows and exterior doors closed while the system is running, so it isn't fighting against warm air constantly coming in. Use ceiling fans to circulate cool air. Just remember to set them to rotate counterclockwise in summer, which pushes cool air downward. Run heat-generating appliances (oven, dryer, etc.) in the cooler morning or evening hours instead of midday. Seal obvious drafts around windows and doors. Insulation and air sealing matter in both the summer and winter, keeping cool air in and hot air out. Will a Heat Pump Increase My Electricity Bill in Summer? The short answer is: maybe a little, but likely not dramatically, and not more than running a comparable standalone AC would. Since a heat pump's summer cooling function works the same way a regular AC does, its cooling-season electricity use is quite similar to a standard central air system of the same size and efficiency rating. Where people sometimes get caught off guard is running the system inefficiently, things like setting the temperature unnecessarily low or constantly adjusting the thermostat, both of which can drive up costs regardless of the system type. As hard as it may be to refrain from, keeping your thermostat at a steady, moderate setting, rather than cranking it down for a quick blast of cold air, is one of the simplest ways to keep summer cooling costs in check. Every degree lower than necessary adds meaningfully to your cooling bill. As a general rule, a range of 21–23°C is recommended for comfortable, cost-effective cooling. The Bottom Line Your first summer with a heat pump should feel a lot less complicated than your first winter. There's no defrost cycles or backup heat kicking in. Just a system that cools your home efficiently as long as it's set up right. Switch to COOL mode, keep those filters clean, resist the urge to crank the thermostat down, and let the system do what it's designed to do. If your current cooling system is struggling to keep up even with these tips, it might actually be time for an upgrade. Our guide on signs your cooling system needs to be replaced can help you figure out if a repair or a full system swap makes more sense. And if you're still deciding between a heat pump and a traditional AC, our explainer on the difference between the two systems and our guide on why you should replace your AC with a heat pump are both great next clicks. Not sure which system is right for your home? Our 3-minute quiz can point you in the right direction, and if you're switching from an older system entirely, don't forget to check our current rebate programs before you book your install, since many provinces still offer some pretty great incentives for heat pump upgrades.
